Slice of Life: Substitution
by The Black Sluggard
Summary: Kevin's POV from "Sublimation", both the events leading up to it, and what followed. PWP. Slash, Ryan/Esposito.


The bad days were few anymore, but that didn't mean they never happened. Kevin had gotten good at spotting them before they did. They often followed the nights when Javier slipped away where he sat, distant eyes staring into dreams he wouldn't later share, or with mornings where Kevin woke early, but still woke up alone. Those days always started off quieter than most, with Javier noticeably distracted, his smile brittle when it shone at all.

Whatever it was that first caught his eye, Kevin paid close attention on those days, though he tried not to seem like he was watching. Quite often nothing happened. Often times they got lucky and something managed to tip Javier out of it. Other days, even if nothing managed to restore the balance, nothing set it swinging in the opposite direction either. And the next day—or the day that followed—was usually a little easier.

Kevin hadn't thought, laying eyes on their crime scene, that today would be one of the lucky ones.

Maintenance men had found the body in a malfunctioning elevator, stalled a few feet short of the basement garage. There was too much blood in that small, cramped space, and too little ventilation. Even on a good day that might have been enough to put Javier on edge. Though his partner stayed calm and admirably composed during their investigation at the scene, he was quiet and tense in that way that always made Kevin think of storm clouds over the horizon.

He had prepared for rough weather ahead.

It only got worse after they picked up their suspect. Uncooperative was too mild a word by half. While it wasn't his partner's usual style, with the state Javier was in the scumbag was lucky he made it into the car without having an "accidental" meeting with the doorframe. In a way _they_ had been lucky. Even when he was vital, Javier had always been good at separating heart-felt insults from antagonistic button-pushing. Their suspect was some cocky, entitled rich kid, the kind who was used to getting away with figurative murder and liked to hear himself talk. A punk, surely, but not a pulse-bigot, not really, and it showed in spite of the slurs he hurled Javier's way.

Still, Kevin winced when the suspect threw out the word "geek". Ever since the rat, Javier had taken that particular epithet a bit personally...

Though Kevin had been all but expecting some sign of strain for the past few hours, the low, soft rumble that trickled out of his partner's throat still managed to catch him off guard. It surprised Javier as well, from the look of it. Javier seemed frozen where he was, still looming over their seated suspect with his palms pressed against the table, not just unmoving but unbreathing. Utterly still in the way only someone who was post-vital could be. For a few moments Javier just stared at the space between his hands before he lifted his head. His face was difficult to read—which was all too often the case, but on days like this even more so—and Javier's eyes slid away from his too quickly for Kevin to decipher whatever emotions lived there. Then he wet his lips and straightened, muttering some vague excuse as he turned toward the door.

Kevin cursed to himself as he shook off his surprise.

"You. _Stay,_" Kevin instructed their suspect, aiming a sharply pointed finger before he quickly followed.

Javier's instinct at times like this was usually to isolate himself—to _hide_, Kevin often forced him to acknowledge after, once his mood had become less volatile. Kevin therefore wasn't surprised to see his partner's back disappearing down the hall, headed, he guessed, for one of the very few quieter parts of the station. He _was_ surprised, however, when he found Javier waiting for him, as though resigned to the fact that Kevin's concern was not something he would ever effectively be able to dodge.

And he was even more surprised with what happened once Javier locked the men's room door behind them.

A kiss covered his mouth, rough, deep and thorough, quickly cutting off any question or protest Kevin might conceivably have leveled. When they broke it left him breathless, and if that hadn't made it difficult enough to form a coherent thought, then the solid press of Javier's weight against his chest—effectively trapping him against the cold bathroom wall—rendered those efforts practically impossible.

"Look, Kev," Javier said, shades of the growl that had escaped him earlier still clinging to his voice, "When we get home we'll talk about this, but for right now..."

And if his partner had begun the sentence with any ending in mind he plainly forgot it, moving in for another kiss. It was slower this time, less urgent—miles still from what could ever be called gentle, but Javier made up for it with a soft press of lips to the edge of his jaw. Then a careful scrape of teeth over the delicate skin of Kevin's throat. Between Javier's fierce attentions and his own initial surprise, it took an embarrassing amount of time for Kevin's brain to catch up enough to join in. As Javier's fingers tangled themselves in the fabric of Kevin's coat, attacking the buttons with newfound purpose, Kevin leaned in to tease an earlobe before he lay an open-mouthed kiss against his partner's neck. Javier responded strongly to the heat of his lips and tongue, just as Kevin knew he would, his quiet focus on opening Kevin's shirt undone by a coarse moan.

Javier's mouth drifted down to his collar bone and Kevin sucked in a breath as cool hands slid past the opening of his shirt. The fingers ghosted lightly over his chest, trembling, Kevin recognized, with a delicate restraint. Javier's attention moved lower, tongue and lips gently teasing Kevin's nipple. Kevin hooked a finger in the waistband of Javier's jeans, sliding his way slowly closer to the front, but as his fingers began their work at the fly he was startled when his partner's hand slapped them away.

"Not yet," Javier murmured against his skin, voice so rough Kevin almost couldn't make out the words. Teeth pulled at the skin beside his nipple, sharp enough to make him gasp. "Want to try something."

Cool saliva grew even colder on Kevin's skin as Javier's mouth traveled downward, and he shivered at the slight sting as Javier tongued the healing outline of the bite beneath his ribs. Chill lips brushed across his navel as Javier sank down onto his knees, fingers tugging at the buckle of Kevin's belt, and as his brain finally caught up with where things were headed rational thought all but fled.

Kevin had done a lot of reading into Javier's condition in the earlier days of his illness, enough to know that skewed perceptions and altered habits were a fact of post-vital life. Even without that background knowledge, Kevin was sure he would have figured it out on his own. The fever that had swept through his partner's body and brain had worked its peculiar magic, destroying or rewriting old neural pathways and creating new ones. While the changes were numerous and in many cases painfully apparent, others were remarkably subtle...

Like the oral fixation that Kevin knew for a _fact_ his partner hadn't possessed when he was warm.

Even those who had known Javier very well before his illness might easily fail to notice. Most of them likely _hadn't_ noticed. But Kevin was a detective—he paid attention—and he had seen plenty of evidence to support his theory. Then again, perhaps the oversight was less an indicator of others' inattentiveness than it was the extra evidence Kevin had at his disposal. After all, beyond the chewed pens and demolished straws, it would have been practically impossible for him not to notice which parts of their private activities Javier seemed to attack with the most passion.

As reluctant as Javier often was to talk about certain aspects of his disease, it was even harder to get him to talk about where it applied in the bedroom. Kevin knew full well it was a minefield of touchy subjects, and generally steered clear whenever they could afford it. Still, though they rarely discussed these things out loud, Kevin thought he had a fair understanding of what Javier liked. And he was uniquely well acquainted with the feel of his partner's lips, tongue and teeth. He didn't think there was any part of him above the waist that Javier hadn't licked, nipped, sucked or bitten, and Kevin therefore thought the leap his mind made was only logical...

Though, in hindsight, the omission was so glaring it really should have been obvious.

The first time it was ever brought up—_suggested_, Kevin would readily admit, in a way that was kind of a request—he could tell Javier had been nervous just thinking about it. Only, it was clearly so much more than nervousness. In fact, judging from Javier's immediate reaction to the idea, _panic_ might even have been more accurate.

_"You're kidding right?"_

Kevin remembered how his stomach had tightened at the words, shame coloring his cheeks. It had been a startled, knee-jerk response, though, and Kevin had forgiven him later. Behind that anxiety, Kevin could see very clearly that it wasn't that Javier hadn't _wanted _to.

Partly, Kevin knew, it was the last remaining shreds of his partner's previous self-identity causing him trouble. Though the physical proof was both plentiful and self evident, it had taken a lot of soothing for Javier to verbally acknowledge that the changes wrought by his condition had made him "a little not straight". While that could have easily seemed petty or insulting, Kevin thought he understood. Javier wasn't ashamed, not of _that_, but IHN had simply forced too many other changes for him to be easily comfortable with any of it.

Then of course there was the issue of safety. For while neither of them would be so crass as to say it out loud, they were both painfully aware of Javier's at times unsteady control, and how certain activities might put parts of Kevin's anatomy—parts of which they were _both_ very fond—at risk.

And Kevin could admit, if only to himself, that the risk itself held it's own strange appeal, but that wouldn't have been possible without trust.

This sudden turn—aggression bleeding away into _passion_—was in sharp contrast with Javier's earlier behavior. Kevin knew that a saner man would have been wary. But he also knew what control looked like. More importantly, he knew what it _felt_ like, and Kevin could feel enough of it in each of his partner's careful movements—_just_ enough—to put him at ease.

Javier's fingers felt impossibly cool against his skin as he drew down Kevin's boxers. He nuzzled his way closer, pausing to suck a dark bruise on the inside of Kevin's thigh, kneading the abused flesh with just a hint of teeth, and the skin of his cheek was so shockingly cold against the heated flesh of Kevin's cock that it drew a faint hiss. Javier brushed the shaft with a light touch of his lips—warmed just slightly by the heat of Kevin's blood—parting them to touch his tongue lovingly to the vein. Javier's attention briefly lingered there, tasting the frantic rhythm of his pulse, before turning his eyes upward, finding Kevin's. Compared with his earlier, aggressive urgency, these careful movements seemed almost shy, an effect exaggerated as Javier looked up at him past half-shuttered lashes.

Apparently finding no sign that would call for him to stop, Javier dipped a cool, tentative lick to the slit of Kevin's cock before his lips closed over the head with just a hint of suction. Everything up to this point had been so hesitant, careful, but the noise Kevin made must have been the best sort of encouragement. His fingers found hard purchase in the meat of Kevin's thigh, and as if acting on cue Javier took him in, suddenly and all the way. Kevin's breath caught, his own fingers digging into Javier's shoulders. Kevin flattened his shoulder blades against the cold tile, bracing as he struggled to control his grip, to keep still. Both efforts seemed painfully in vain, and Kevin distantly—very, _very _distantly—despaired of the fact.

Javier bruised very easily these days, though it no longer showed.

If Kevin hurt him at all, Javier never made a noise to show it. In fact, Javier hardly made any noise at all. Over his own ragged breathing, Kevin could hear a few soft, wet sounds, but other than that there was nothing. Of course, it wasn't as if Javier had any need to breathe, but Kevin sensed it was more than that. He was critically aware of the level of focus it often took Javier to control himself. Lifting a hand from Javier's shoulder to cradle his face, Kevin could feel the tension that was building in the muscles, the taut energy in the flex of his partner's jaws.

And perhaps that touch, the warm brush of Kevin's thumb over the cold skin of his cheek, broke his concentration just a little. There was a light scrape of teeth, just a whisper of pressure, and Kevin couldn't stop the shallow thrust of his hips. It was a reaction that could have proved disastrous, but fortunately for both of them Javier had no gag reflex—and that detail should _not_ have been sexy, given Kevin's awareness of how the knowledge had been gained, but somehow it still _was_. For his part, Javier hardly seemed to notice, though it drew an odd sound from deep in his throat. A growl—well, possibly. It was so obscenely muffled that it as difficult to tell.

And whatever it was Kevin was certain it was involuntary, but the _vibration_—

"Jesus. _Javi_..."

The words, choked off with a gasp, were the only warning Javier got. Still, he must have known Kevin was close, because he pulled off just a little. Kevin came shortly after, feeling the slight pull as Javier swallowed. Kevin melted back, letting the wall support his weight as he struggled to catch his breath. And Javier drew off very suddenly, his fingers digging in where they gripped Kevin's thighs, and a breathless grunt escaped him before he dug his teeth into the sharp corner of Kevin's hip. Kevin let out a shocked gasp at the pain that bloomed from the bite. Javier shuddered with a convulsive jerk before he released his teeth and fingers and was left leaning heavily against Kevin's body.

Javier's eyelids fluttered softly where his face was pressed against the skin at Kevin's waist, and after a slow moment his partner looked up at him, dazed. While he wasn't breathing heavily he wore that sex-drugged expression that Kevin had grown accustomed to. Kevin came to the startling realization that Javier was finished as well, and was forced to fight off a flash of childish disappointment that he'd barely even had the chance to touch him. Not that he was left _wanting_...he just hoped that Javier could say the same.

Rather than dwell on it, he settled for a careful exploration of the bite instead.

It was just deep enough to break the skin and not bleed, aching when he pressed even lightly against it. Kevin knew the bruise would be dark and purple by the time they got home. He dialed down his pleased smile before he let his eyes travel down to where Javier still rested, a cold, solid weight against his legs. And Javier _was_ looking up at him, a faint, shocked disbelief in his eyes. His fingers were already cooling back to room temperature after their contact with Kevin's skin, noticeably chill as they passed over the damaged flesh.

"Shit..._shit_, Kev, I'm sorry—"

"For _what_?"

Which may have been the wrong response, Kevin wasn't sure, but if nothing else it was an honest one. If it was needed he would regret it later. Right now they badly needed to get themselves sorted. His hand on Javier's cheek drew his partner's attention away from the damage inflicted and up to his eyes, and Kevin did his best to return just _how_ okay he was with his gaze and a soft smile. From the way the embarrassment and uncertainty gradually faded from Javier's expression, maybe it even helped. They moved from there to the task of raising Javier to his feet, to assessing both their sorry states, and deciding just what needed to be done about it.

Aside from the wrinkles in his coat, Kevin had come out of it mostly intact—where it showed—though he was dismayed to realize his shirt had lost buttons. The shirt wasn't a favorite of his, but he hoped against hope that Castle and Beckett wouldn't notice. Javier's slacks were pretty much a loss. And as Javier went off to change, Kevin headed back to interrogation, planning as he went for that _talk_ his partner had promised to have once they got home...

Because if Kevin had any say, it was going to take place against the first hard surface he could find.


End file.
